1. Field of the Invention
The present invention relates to a fixing apparatus for a printer, and more particularly, to a fixing apparatus for a printer, the fixing apparatus having a paper separating unit that can prevent elements from being worn and which can be manufactured at low cost.
2. Description of the Related Art
FIG. 1 is a cross-sectional view of a conventional fixing apparatus for a printer having a paper separating unit and a paper ejecting apparatus. Referring to FIG. 1, the conventional fixing apparatus includes a heating roller 11, a pressing roller 13, a paper separating unit 15, and a tension spring 17. The heating roller 11 fixes an image on paper S by heating the paper S on which the image developed by a conventional developing unit (not shown) is formed. The pressing roller 13 helps to fix the image by pressing the paper S that contacts the heating roller 11 and which is inserted in an interface with the heating roller 11. The paper separating unit 15 contacts the heating roller 11 and separates the paper S. The tension spring 17 applies an elastic force to the paper separating unit 15 and maintains the paper separating unit 15 in a correct position.
The image on the paper S passes through the fixing apparatus, is fixed on the paper S, and is then moved to the paper ejecting apparatus via a paper ejecting guide 25. The paper ejecting apparatus ejects the paper S, which is supplied while first and second ejecting rollers 21 and 23 rotate in contact with each other, to the outside.
FIG. 2 is an enlarged view of portion A of FIG. 1 and shows a contact surface between the paper separating unit 15 installed in the conventional fixing apparatus for a printer and the heating roller 11. Preferably, the conventional paper separating unit 15 should form a sharp end, to contact the heating roller 11 closely and to separate the paper. However, in general, the conventional paper separating unit 15 is formed of plastics having a blunt end, as shown in FIG. 2. In such a case, while the paper separating unit 15 operates, the surface of the heating roller 11 is damaged by the blunt end of the paper separating unit 15, causing image quality to deteriorate.
Also, since the heating roller 11 of the conventional paper separating unit 15 operates at a temperature of about 180 C, the paper separating unit 15 is formed of a material resistant to heat even at a high temperature In addition, TEFLON® is coated on the surface of the paper separating unit 15. As a result, the manufacturing cost of the paper separating unit 15 is greatly increased.